Gold­man Sachs, in a re­port, said talk of an out­put freeze by the Or­gan­i­sa­tion of the Pe­tro­leum Ex­port­ing Coun­tries and a weak dol­lar had helped drive prices up this month but nei­ther was enough to sus­tain cur­rent lev­els.

Oil prices have more than halved from mid-2014 due to a global sup­ply glut.